1. Field of the Invention
The present invention relates to a bearing retainer for a vacuum cleaner motor, and more particularly to a bearing retainer for toolless insertion within a motor housing which reliably secures a stock bearing assembly within the motor housing with no additional machining steps, bearing mounting parts or added processing required.
2. Description of the Prior Art
In conventional form, one-piece corrugated bearing retainers for securing a motor shaft bearing assembly within a motor housing are well known. An example of such a retainer is that made and sold under the commercial name USA Tolerance Rings Part No. ANL 22X7-S. Such bearing retainers typically are formed of stainless steel in an elongated rectangular shape, and are sufficiently flexible at room temperature to permit them to be deformed into an annular shape for toolless insertion into a motor housing.
A previously unresolved problem, however, has limited their usefulness in securing bearings subject to the high shaft speeds, high frequency vibrations, and the bearing housing draft angles encountered in vacuum cleaner motor applications. The drawback to current corrugated bearing designs is that there is a tendency to "creep" from between the bearing and the associated housing, thus causing the bearing to become displaced or misaligned in the housing, thereby causing premature bearing or motor failures.
Previous attempts at solving the generic problem of securing a bearing retainer within a housing can be found on bearing retainers of the non-corrugated type. One prior art solution is to use the bearing retainer to physically block the path of the bearing assembly to prevent escape from the motor housing. Another prior art solution is the use of spring tension to secure the bearing within the motor housing. The latter solution is unsatisfactory, however, since it typically requires the use of metal not found in the present bearing retainer capable of generating large spring forces, and the bearing retainer tends to lose spring force over time. The former solution is unsatisfactory in a corrugated bearing retainer since it requires costly additional machining to the bearing assembly, motor housing, or both.
U.S. Pat. Nos. 4,710,037, 4,364,615 and 4,236,767 are examples of bearing retainers using spring force to secure the bearing within the hub or housing. U.S. Pat. No. 4,710,037 includes the additional disadvantage of requiring a tool for assembly, and U.S. Pat. No. 4,364,615 has the additional disadvantage of requiring machining of the housing, as shown in FIG. 7. The spring shown in U.S. Pat. No. 4,236,767 is integral to the bearing, and obviously not useable with a stock bearing assembly.
U.S. Pat. Nos. 4,545,627 and 1,906,521 disclose bearing retainer devices using snap rings fit in a groove located in the bearing or the housing. These designs have the disadvantage of requiring additional machining of the bearing or the housing, and further do not compensate for manufacturing tolerances between the bearing and housing.
The present invention overcomes these problems of prior bearing retainer devices in a novel and simple manner.